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Effect of deposition time on surface plasmon resonance and Maxwell-Garnett absorption in RF-magnetron sputtered carbon-nickel films

Dalouji V.

Materials Science Poland

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2016

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Vol. 34, No. 2

337--343

EN

In this work, carbon-nickel films were grown during four deposition times (50 s, 90 s, 180 s and 600 s) at room temperature on glass substrates by radio frequency magnetron sputtering. The optical absorption spectra of the films were investigated with a special emphasis on the surface plasmon resonance (SPR) of Ni nanoparticles. The optical absorption peaks caused by the surface plasmon resonance of Ni nanoparticles were observed in the wavelength range of 300 nm to 330 nm. It has been shown that the surface plasmon resonance peaks exhibit a red shift and a blue shift depending on the deposition time. The red and blue shifts of the surface plasmon resonance in the absorption spectra of the films were observed with the increase and decrease of Ni nanoparticle size, respectively. The Ni nanoparticle size, dielectric function of carbon matrix εm and plasma frequency of free electrons ωp for the films deposited at deposition time of 180 s have maximum values of 80 nm, 0.401 and 7.25 × 1015 s–1, respectively. These observations are in a good agreement with the electrical resistivity measurements and Maxwell-Garnett (M-G) effective medium theory (EMT)

2

Electroless deposition of Ni-P/nano-Al2O3 composite coatings on PET and carbon fibres substrates

Sałacińska A., Bieliński J., Zawadowska M., Kozera R., Boczkowska A., Kurzydłowski K. J.

Composites Theory and Practice

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2012

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R. 12, nr 2

86-92

EN

This paper presents the results of studies on the electroless deposition of Ni-P/nano-Al2O3 composite coatings on pretreated polymeric bases (PET polyester Mylar A type) and on carbon fibres (24k fibres with 7 &m Tenax rovings). The Ni-P matrix was deposited from a solution consisting of NiSO4 0.1 M; NaH2PO2 0.2 M; glycine 0.21 M, with a pH = 7.5 8.5 and thiourea added as a stabilizer, as well as cetyltrimethylammonium bromide as a surfactant. Aluminium oxide C (DNC - Degussa, grains 13 nm) or A16 (Alcoa, grains 400 nm) were powders amounting to 10 30 g/l, with ultrasonic homogenization of the suspension. Under the experimental conditions applied, partial sedimentation of the A16 powder occurred, thus a furtherstudy on carbon fibres metallization was performed with the use of the DNC nanopowder. Deposition was performed in the temperature range 60 70oC, during 5 60 minutes, while the bases rotated at 1 rpm and the suspension was agitated with a stirrer. The composition of the deposited layers was determined by chemical methods and their surface morphology was investigated using SEM. A procedure for the preparation of the PET substrates for the tests was set out to obtain good adhesion of the Ni-P layers. Under the applied conditions, Ni-P/Al2O3 layers of a thickness within 130 720 nm, aluminium oxide content up to 25% by weight, and 2 4% phosphorus by weight were obtained.

PL

W pracy przedstawiono wyniki badań nad bezprądowym osadzaniem warstw kompozytowych Ni-P/Al.2O3 na podłożach polimerowych typu Mylar (poliester PET) oraz na włóknach węglowych (wiązki 24k włókien 7 žm Tenax). Osnowa Ni-P osadzana była z roztworu NiSO4 0,1 M; NaH2PO2 0,2 M; glicyna 0,21 M, o pH = 7,5÷8,5 z dodatkiem tiomocznika jako stabilizatora oraz bromku cetylotrimetyloamoniowego jako surfaktanta. Dodawano proszków tlenku glinu Aluminiumoxide C (DNC - Degussa, ziarna 13 nm) lub A16 (Alcoa, ziarna 400 nm) w ilości 10÷30 g/l, z ultradźwiękową homogenizacją zawiesiny. W zastosowanych warunkach doświadczeń stwierdzono częściową sedymentację proszku A16, stąd dalsze badania nad metalizacją włókien węglowych prowadzono z nanoproszkiem DNC. Osadzanie prowadzono w zakresie temperatur 60÷70oC, w czasie od 5 do 60 minut, podłoża obracały się z szybkością 1 obr/min, a zawiesina mieszana była mieszadłem magnetycznym. Określano chemicznie skład osadzanych warstw oraz morfologię ich powierzchni za pomocą SEM. W próbach z podłożami PET ustalono procedurę przygotowania tego materiału dla uzyskania dobrej adhezji warstw Ni-P. W zastosowanych warunkach osadzone bezprądowo warstwy kompozytowe Ni-P/Al2O3 o grubości 130÷720 nm zawierały do 25% mas tlenku glinu oraz 2÷4%mas fosforu.

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Inversion of the Jacobi-Porstendörfer room model for the radon progeny

Thomas J., Jílek K., Brabec M.

Nukleonika

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2010

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Vol. 55, No. 4

433-437

EN

The Jacobi-Porstendörfer (J-P) room model describes the behaviour of radon progeny in the atmosphere of a room. It distinguishes between free and attached radon progeny in air. It has been successfully used without substantial changes for nearly 40 years. There have been several attempts to invert the model approximately to determine the parameters describing the physical processes. Here, an exact solution is aimed at as an algebraic inversion of the system of six linear equations for the five unknown physical parameters k, X, R, qf, qa of the room model. Two strong linear dependencies in this system, unfortunately do not allow to obtain a general solution (especially not for the ventilation coefficient k), but only a parameterized one or for reduced sets of unknown parameters. More, the impossibility to eliminate one of the two linear dependencies and the departures of the measured concentrations forces to solve a set of allowed combinations of equations of the algebraic system and to accept its mean values (therefore with variances) as a result of the algebraic inversion. These results are in agreement with results of the least squares method as well as of a sophisticated modern statistical approach. The algebraic approach provides, of course, a lot of analytical relations to study the mutual dependencies between the model parameters and the measurable quantities.

4

Studying of kinetic growth of organic thin films

Weszka J. P., Jarka P., Pakuła D., Dobrzański L. A., Domański M., Jurusik J.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 35, nr 1

29-36

EN

Purpose: of this paper: Studying of growth kinetic of organic thin film prepared by vacuum thermal evaporation technology. Design/methodology/approach: Applying of quartz crystal microbalance to thickness control of organic thin films deposition process. Findings: Results of this issue suggesting that the kinetics of organic thin films is depending of current flowing through the crucible (crucible temperature). Research limitations/implications: Kinetics of vacuum evaporation of thin film is different from that of inorganic thin films during the growth process. Practical implications: The means of connect the quartz crystal microbalance MSV 1843/AB with vacuum chamber, function and means of thickness and deposition rate measuring has been described. This scientific paper include also description of researching results of kinetics of organic and metallic thin film evaporation process by MSV 1843/AB quartz crystal microbalance and verification these results by comparing them with results from other measuring techniques. Originality/value: Controlling thickness of thermally evaporated organic thin film during the film growth process.

5

Analiza tempa depozycji materiału detrytycznego w basenach sedymentacyjnych zachodnich Karpat zewnętrznych jako wskaźnik aktywności tektonicznej ich obszarów źródłowych

Poprawa P., Malata T., Oszczypko N., Słomka T., Golonka J., Krobicki M.

Przegląd Geologiczny

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2006

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Vol. 54, nr 10

878-887

EN

Analysis of deposition rate were performed for synthetic sections, representing the upper Jurassic to lower Miocene sedimentary fill of the Western Outer Carpathian (WOC) basins. Calculated deposition rates differs in a range of a few orders of magnitude. During Tithonian to Berriasian-early Valanginian tectonic activity of the source areas supplying the Silesian Basin was related to the mechanism of syn-rift extensional elevation and erosion of horsts. General decay of source area activity in Valanginian to Cenomanian time was caused by regional post-rift thermal sag of the WOC. The Barremian to Albian phase of compressional uplift of the source area located north of the WOC lead to increase of deposition rate in some zones of the WOC basin. In Turonian to Paleocene time thick-skinned collision and thrusting took place south and south-west (in the recent coordinates) of the Silesian Basin causing very rapid, diachronous uplift of this zone, referred to as Silesian Ridge, resulting with high deposition rate in the Silesian Basin. At that time supply of sediments to the Magura Basin from south was relatively low, and the Pieniny Klipen Belt was presumably zone of transfer of these sediments. In Eocene the zone of collisional shortening in the WOC system was relocated to the south, causing rapid uplift of the Southern Magura Ridge and intense supply of detritus to the Magura Basin. Thrusting in the Southern Magura Ridge and collisional compression resulted with flexural bending of its broad foreland, being the reason for decrease of activity of both the Silesian Ridge and the source area at the northern rim of the WOC. The Eocene evolution of the Silesian Ridge is interpreted as controlled by both episodic tectonic activity and eustatic sea level changes. Contrasting development of the Southern Magura Ridge and the northern rim of Central Carpathians during Eocene stands for a palaeographic distance between the two domains at that time. During Oligocene and early Miocene a significant increase of deposition rates is observed for the basin in which sediments of the Krosno beds were deposited. This was caused by tectonic uplift of the source at the northern rim of the WOC, as well as the Silesian Ridge and the partly formed Magura nappe. The Miocene molasse of the WOC foredeep basin is characterised by notably higher maximum deposition rates than ones calculated for the flysch deposits of the WOC.